1. Field of the Invention
The invention relates generally to an improved design of sliding block puzzles.
2. Description of Prior Art
Sliding block puzzles may be loose blocks that slide around in a tray. Any one or more blocks may be lifted out of the tray or may be dumped out of the tray by turning it upside down. The problem with loose blocks is that they can spill out unintentionally and get lost.
Another design of sliding block puzzles may be of tongue and groove construction on the sides of each block and on the frame of the tray so that once assembled, the blocks can slide against each other and against the frame. The tongue and groove have them locked into each other and the frame so that any one or more blocks cannot be lifted out of the tray, nor can they be dumped out of the tray by turning it upside down, nor can they be removed in any way short of disassembly of the manufacture. While this self-containment solves the problems of spillage and loss, the problem is that the user cannot remove and rearrange blocks for a fresh start.